In this study, the antibacterial activity of cerium oxide nanoparticles on two Gram-negative and three Gram-positive foodborne pathogens was investigated. CeO₂ nanoparticles (CeO₂ nps) were synthesized by a Wet Chemical Synthesis route, using the precipitation method and the Simultaneous Addition of reactants (WCS–SimAdd). The as-obtained precursor powders were investigated by thermal analysis (TG–DTA), to study their decomposition process and to understand the CeO₂ nps formation. The composition, structure, and morphology of the thermally treated sample were investigated by FTIR, Raman spectroscopy, X-ray diffraction, TEM, and DLS. The cubic structure and average particle size ranging between 5 and 15 nm were evidenced. Optical absorption measurements (UV–Vis) reveal that the band gap of CeO₂ is 2.61 eV, which is smaller than the band gap of bulk ceria. The antioxidant effect of CeO₂ nps was determined, and the antibacterial test was carried out both in liquid and on solid growth media against five pathogenic microorganisms, namely Escherichia coli, Salmonella typhimurium, Listeria monocytogenes, Staphylococcus aureus, and Bacillus cereus. Cerium oxide nanoparticles showed growth inhibition toward all five pathogens tested with notable results. This paper highlights the perspectives for the synthesis of CeO₂ nps with controlled structural and morphological characteristics and enhanced antibacterial properties, using a versatile and low-cost chemical solution method.

Our study is focused on the structural and morphological characteristics, optical behaviour and photocatalytic properties of undoped and 5 at% Eu³⁺-, Gd³⁺- and Y³⁺-doped CeO₂ nanoparticles prepared by a green hybrid sol-gel combustion method. Several techniques such as X-ray diffraction powder (XRD), Transmission Electron Microscopy (TEM), UV-Vis spectroscopy, Photoluminescence spectroscopy (PL) and Electron Paramagnetic Resonance (EPR) have been used to investigate the obtained samples. Moreover, the correlation between the characteristics and properties has been studied. The nanoparticles observed by TEM exhibit a pseudo-spherical shape, except for Y³⁺-doped CeO₂, which presents an acicular shape. The average size of undoped and rare-earth-doped CeO₂ nanoparticles is below 10 nm, in good agreement with the calculations performed based on XRD analyses. From UV-Vis analyses it has been deduced that with doping the band gap energy decreases, which shows that additional levels are introduced by doping into the CeO₂ band gap. The EPR spectra evidence similar behaviour for all doped samples. The photocatalytic activity was evaluated by the degradation of rhodamine B (RhB) under UV light irradiation. The photodegradation mechanism has been studied in depth based on the formation of electron-hole pairs, and to evidence the reactive oxygen species, ESR coupled with spin-trapping experiments was performed. In the case of Y-doped CeO₂ nanoparticles, the generation of both •OOH and •${\mathrm{O}}_2^{-}$ radicals involved in RhB photodegradation was highlighted.

Background/Objectives: Iron deficiency anemia remains a primary global health concern, affecting millions worldwide. Despite the widespread availability of iron supplements, their efficacy is often hindered by poor bioavailability and adverse gastrointestinal effects. This study explores the potential of probiotics to enhance the bioavailability of Fe₃O₄ NPs through probiotic-mediated mechanisms. Methods: Lactobacillus fermentum, Lactobacillus rhamnosus, and Lactobacillus plantarum were utilized to investigate their interactions with Fe₃O₄ NPs, synthesized via co-precipitation and characterized using transmission electron microscopy, scanning electron microscopy, Fourier transform infrared spectroscopy, and X-ray diffraction. Results: The results indicated that probiotics adhere to the nanoparticle surface, with L. fermentum exhibiting the highest adhesion and internalization capacity, leading to a significant increase in 4-hydroxyphenylacetic acid (4-HPLA) production (11.73 ± 0.09 mg/mL at 24 h, p < 0.05). Spectroscopic analyses further revealed that probiotic metabolism facilitates the oxidation of Fe₃O₄ to Fe₂O₃. Additionally, Fe₃O₄ nanoparticle-treated cultures demonstrated enhanced bacterial viability and metabolic activity, highlighting a synergistic effect between probiotics and iron nanoparticles. Conclusions: These findings provide compelling evidence for probiotic-assisted iron supplementation as a promising strategy to enhance iron bioavailability while mitigating the gastrointestinal side effects of conventional iron supplements.

Our study is focused on optimizing the synthesis conditions for the in situ oxidation of Fe particles to produce Fe@Fe₃O₄ core–shell powder and preparation via co-precipitation of ZnFe₂O₄ nanoparticles to produce Fe@Fe₃O₄/ZnFe₂O₄ soft magnetic composites (SMC) through a hybrid cold-sintering/spark plasma-sintering technique. XRD and FTIR measurements confirmed the formation of a nanocrystalline oxide layer on the surface of Fe powder and the nanosized nature of ZnFe₂O₄ nanoparticles. SEM-EDX investigations revealed that the oxidic phase of our composite was distributed on the surface of the Fe particles, forming a quasi-continuous matrix. The DC magnetic characteristics of the composite compact revealed a saturation induction of 0.8 T, coercivity of 590 A/m, and maximum relative permeability of 156. AC magnetic characterization indicated that for frequencies higher than 1 kHz and induction of 0.1 T, interparticle eddy current losses dominated due to ineffective electrical insulation between neighboring particles in the composite compact. Nevertheless, the magnetic characteristics obtained in both DC and AC magnetization regimes were comparable to those reported for cold-sintered Fe-based SMCs.

Luminescent materials, or phosphors, are organic, inorganic, or hybrid organic/inorganic systems that convert certain types of energy into electromagnetic radiation over thermal radiation

Natural-based and synthetic tissue adhesives have attracted extensive attention in the last two decades for their ability to stabilize uncontrolled bleeding instances. However; these materials present several drawbacks during use that scientists have tried to minimize in order to optimize their usage. This study comprises the development of a novel wound dressing, combining the excellent properties of polylactic acid (PLA) non-woven textile, as substrate, obtained through electrospinning, and a cyanoacrylate-based (CA) tissue adhesive, for rapid hemostatic action. Thus, the fabrication of electrospun PLA membranes at three different PLA concentrations, the design and manufacturing of the support system and the production of surgical patches were carried out. SEM and FT-IR methods were employed for analyzing the morphology as well as the indicative markers for the shelf life evolution of the obtained patches. PLA fibers with well-defined structures and a mean diameter varying between 4.6 and 7.24 μm were obtained with the increase of the concentration of the PLA solutions. In vivo tests on a rat model as well as peeling tests for good patch adhesion on liver fragments harvested from the test animals, with a limit for the strength of the liver tissue of 1.5 N, were carried out. The devices exhibited excellent adhesion to the parenchymal tissue and a long enough shelf life to be used with success in surgical procedures, also facilitating prompt hemostatic action.